Almost a month in the Bing It On campaign comparing Google and Bing search results, Microsoft said more than 5 million people took on the challenge, with early results indicating a majority of people preferred Bing’s results.

The results showing people liked Bing’s results better are not based on the 5 million visitors to the campaign website. Instead, Microsoft hired an independent company, Answers Research, to take a survey of users impressions before and after they took the Bing It On challenge, a blind test comparing Google and Bing organic search results.

The survey covered some 4,700 people and found that 64 percent of people were surprised by the quality of Bing’s search results. More than half the people surveyed indicated that their impression of Bing improved after seeing Bing’s Web search results next to Google’s. Also, 33 percent of those who identified themselves as primary Google users said that they would use Bing more often after taking the challenge.

Microsoft did not reveal the full extent of public opinion on Bing from the 5 million visits it had to the site, but if the survey was any indication of the general results, then 17 percent of those who found Bing more favorable after taking the side-by-side comparison said it revealed flaws in Google’s results.

Mike Nichols, Bing’s chief marketing officer, admitted in a blog post that it will be hard for many people to stop using Google: “Of course, the ‘Google habit’ is strong in many people and habits don’t change overnight. We are working very hard to continue improving the quality of our results (from Web search to adding new useful information from your social networks), and to make the distinctions between Bing and Google clear so you can make an informed choice.”

Although the number of people surveyed by Microsoft might be too small to be an indication of how Google is perceived compared to Bing, what the campaign reflects is that Bing is a capable search engine. Meanwhile, Google remains the dominant search engine in the world with more than 85 percent share in the U.S. and global, and Bing’s efforts will only slowly chip away at Google’s popularity.